


Lack of Resistance and All Reward

by Kisuru



Category: Naruto
Genre: Alpha Uchiha Itachi, Alpha/Beta/Omega Dynamics, First Time, Knotting, M/M, Marking, Mating Cycles/In Heat, Mildly Dubious Consent, Omega Uchiha Sasuke, Protectiveness, Scent Kink, Sibling Incest, Smut
Language: English
Status: Completed
Published: 2019-07-24
Updated: 2019-07-24
Packaged: 2020-07-12 13:07:43
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 3,137
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/19946668
Author URL: https://archiveofourown.org/users/Kisuru/pseuds/Kisuru
Summary: Sasuke's first heat arrives and the pain is too unbearable for him to endure. Itachi, ever the most observant of the changes his little brother faces even while he is in the Akatsuki, is not willing to let another alpha give him the pleasure he deserves.





	Lack of Resistance and All Reward

**Author's Note:**

> It’s July 23rd right now, so happy birthday, Sasuke! I've always wanted to post something on a character's birthday. Well, this isn’t a birthday fic in its themes or anything per se, but Sasuke gets his heat taken care of. So yay? Canon events may or may not have gone down the same. Idk, this is a simple smut A/B/O thing.

Leaning forward, Sasuke ungainly clutched his abdomen. At first he had hoped it would curb the persistent aches rising and falling under his skin in acute waves. Overcoming the heat with persistence wasn’t working. Vigorously, he shook his head, breathing rapidly to snap himself out of the feverish-induced daze plaguing him. The oncoming pain had been gradual for the course of several days. The simmering onslaught of agony and need were wholly unbearable.  
  
Wary, he suspiciously eyed the vivid red cloud on the Akatsuki cloak before him. His brother found him. It mocked him endlessly he was in such an unguarded position, or lacked the will to try escaping him in his condition; his head throbbed for the disadvantages. He would not let him come anywhere close. Not like this.  
  
Twinges of curiosity welled within Itachi. The temptation of his heat was the only thing he had yearned for ever since his scent spiked in intensity and enticed him from the shadows for the real deal. He swallowed the dry lump of excitement locking the back of his throat in thick ties. “Your first heat, little brother?”  
  
Sasuke scowled. With the extra effort, the scenery whirled in his vision. He staggered. His voice, the person he missed and hated—why did that voice make him want walk over to him as though a command drove him?  
  
“Shut up!” Sasuke hissed. He gritted his teeth. His heart drifted on the edge of bursting at the seams with its incessant beats. He balled up his fists, enduring the impulse to pounce. The potent, hardy scent his brother exuded caused his skin to crawl with unbridled desire. He craved skin contact so, so desperately. “Don’t… dare look… dare... D-Damn…!”  
  
He hadn’t realized the bastard stalked him into the forest after he had left the hideout. Sasuke had been too delirious with the fire in his veins. Hoping to locate a secluded area and ignore the need racking his body head to toe, he saw that wasn’t an option anymore. Not with him there. Itachi, closer than he was willing to admit he helplessly wanted him to be with a predatory gaze, awakened both hopes of their old bond and primal urges.  
  
Itachi stepped forward. “I will help you.”  
  
“I’ll never need your help,” Sasuke shot back. Another strong wave of heat barreled through his chest. White stars twinkled in his eyes. No, he was strong enough to defeat the heat! He had always endured, so he would, he _must_ —  
  
“Am I wrong? Your eyes tell me the opposite,” Itachi said. To him, no further truth existed. The observation was honest; his ravenous, dilated pupils did unspeakable things to his ego, knowing he was far gone for him. The desire in his expression and body stance had more or less tripled since he had shown signs he knew that he was there within the vicinity.  
  
He bridged the short distance and shed the dark cloak with a shrug in the blink of an eye. Sasuke’s mind went blank, hypersensitive to the point he automatically made eye contact. He focused on the Sharingan’s tomoe when his face was suddenly inches away from his. Once again, he was mesmerized with Itachi’s strict, bone-chilling attention like always.  
  
An incoherent jumble of emotion and words jammed in his brain, and the protests folded on his tongue, weak and brittle. Sasuke was torn between hate and drowning love for the heat radiating off his body, vastly familiar yet unattainable for years. His steps backwards were instinctive at best. A patch of weeds under his sandal blocked his path and tangled around his foot. Balance lost, he stumbled, his back hitting the boulder behind him.  
  
A hand fell on his shoulder, pinning him there, though Sasuke didn’t know where he would escape to anyway. Itachi’s left hand spent no time dawdling, snatching and twisting the rope belt on Sasuke’s pants to free the cloth around his middle. Both fell alongside the sheath for his sword on the ground at their feet. His fingers dipped into the band of his pants. Positively shivering, Sasuke cursed himself for not having the foresight to prevent his vulnerability while still not fighting back when he had ample chance to push him.  
  
Itachi caught himself before his body acted without his consent. Impulse demanded he kiss him, make the press of their lips deep and forceful—but, he reminded himself, he didn’t necessarily need cruelty for regret to creep up and settle in his heart for giving into base feelings. Perception of failure was worse than a knife churning in his chest. He bit his lip. If he gave into temptation he wouldn’t stop himself for who knows how long. He wanted to prolong their meeting in every way possible, but he needed the main event _now_.  
  
“Who knew you were dreadfully shameless,” Itachi whispered in his ear, rubbing salt in his wounds. He pulled the thin waistband of his pants and underwear down his thighs; fingers skimmed his skin, earning him the delight of twitching muscle under his touch. “I smelled you a mile away. Don’t act high and mighty. You want me to take you where you stand.” It wasn’t simply a method of attack for giving in, though. He was helplessly aroused. It served to turn him on further than he imagined, and any control of his own preservations was lost.  
  
Devising his brother was at the right age for intimacy, to find a mate—Itachi had waited. Watching and hoping to be first. To his relief, Sasuke had not shown interest in anyone else, and that set the stage for them. He hadn’t let anyone touch him yet and the muddled spray of pheromones in the air proved the fact. He knew he couldn’t let him stay in pain, riding out his desires without promise of pleasure.  
  
Mouth parting, Sasuke moaned loudly under him. His smugness was undeniable; his filthy little secret was a frightening truth. He tuned him out, but the words sent jolts to his groin on the peak of no return. He face brightly flushed. Through lightheaded dizziness, he zoned in on Itachi’s face—and he was too _appealing_. Before his body caught up with his short-circuited brain and took action on that itch to touch him, Itachi swiftly gripped his forearm, spun him, and shoved him face-first into the rock. His pants fell past his knees. His lower half was revealed, the insatiable source of his carnal high. He was greeted with cloying sweetness filling the air that betrayed Sasuke’s attempts to hide his lust further.  
  
Should another alpha smell his delectable, airy scent, Itachi wouldn’t forgive himself. The intoxicating scent made him heady, on the verge of saying he was in heaven. No other alpha could claim Sasuke properly if he were ambushed in his current state. Itachi knew they would get the wrong ideas about him and hurt him. Worse, he was irritated they would imagine handling him at all.  
  
He was the only suitable one to be with him. Itachi would never forget his scent no matter how long they were separated. The fact it was his beloved brother’s first time, a significant life-changing memory, added to his incentive to act the best alpha a hundred times over.  
  
Sasuke’s expression morphed into a snarl. He was not given a chance for rebuttals, because he heard a faint slip of cloth. Itach’s fingers slipped and locked in his hurry, the straining tent in his pants thinning his patience. At his breaking point, Itachi yanked the fabric down his legs and freed himself from the confines. The vibrations of a low growl rumbled near Sasuke’s ear. He licked his lips in anticipation despite the underlying horror (the fear was irrelevant in the name of the horniess) he was handing himself over on a silver platter for his greedy brother to do as he pleased with him.  
  
He pushed into his upper back and pinned him with weight. Briefly, he was ambivalent. He had never taken another mate. Only an _impeccable_ debut was permittable—Itachi accepted no less for his brother, and he would learn that submission under his strength was inevitable. His grand plans crumbled almost instantaneously, though, for Sasuke was at arm’s length. Thinking beyond his warmth was impossible. Pure instinct guided him.  
  
_Don’t worry, Sasuke_ , he thought. _I have you_.  
  
The tip nudged him—and the brush of soft flesh was hot, the center of Sasuke’s world within a flash. To meet him, he spread his legs. It dawned on him how ready he was; he dripped in invitation. He was ready to scream, but the sound stayed trapped in his throat. For all the insufferable his brother was, he had no idea what to expect (or why he chose that moment to be close), but… He couldn’t stand it! The last thing he would tolerate was the brutal, slow torture to make him beg for release, or illusions of feigned gentleness.  
  
“Don’t taunt me,” he snapped.  
  
The raspy sound of his voice was to die for. Itachi’s chest did a flip. He forced himself not to reveal how much taunting and teasing he wished he would shower him in. “Big words,” he mused. “How will you feel when you won’t be able to walk after I’m through with you?”  
  
Sasuke heaved a long-suffering sigh, because his body demanded that, though half denied he would ever be brought down to that level.  
  
He wanted at least that much stability. That bit of sensibility was all he could offer. Hands falling to his hips to keep him in place, Itachi braced himself. With a jerk of his hips, he entered him from behind, relishing the slick that easily greeted him on the way in. It wasn’t the initial smooth sailing he expected—but, _oh_ , the solid resistance was a delightful shock, realer than his own illusions to satiate his drive. The tight muscle and round cheeks squeezing his cock. And the sweet heat…  
  
His grip on him wavered, awestruck, flushing a smidge out of doubt. (Thank their positions for the fact he could not see his face.) Right off the bat he didn’t know where to move first and how hard. He was as inexperienced as he was—the struggle to avoid needless mates and focus on his brother’s growth from afar had been intense due to cravings—though the movements would come naturally. Try as he might, he couldn’t think clearly, and he _had_ told himself he wouldn’t slip up twice! Instinct demanded he embrace the recklessness, but how could he be reduced to mindlessness?  
  
Sasuke’s vision blurred. He gasped, thrashing under him. Spreading his legs wider when he thrust into him, his feet wobbled with the new intrusion. Pent up with need he didn’t know what to do with, he clawed at the boulder, nails digging in the surface, leaving small trails in their wake. Tears formed in his eyes but not out of anger. He stretched him past the limits he had ever been, filled him up.  
  
Even through half-lidded eyes, his frenzied hand motions hypnotized him. Stiff, white knuckles and worn fingernails anchored on the rock. His head bobbed back and forth. Muffled whimpers set his blood ablaze. His brain sizzled with protective mercilessness—nothing else mattered, he must make this good for them both—and he gave into that urge wholeheartedly. And his slow, adjusting pace increased, and he lost conscious effort to keep rhythm. He pulled back and slammed into him, deeper, doing it again and again.  
  
The strength in Sasuke’s body slackened. His cheeks shone a brilliant red. His expression dropped into wistful relaxation. The stress of his aches dissolved, and wound muscles that demanded such treatment thrived in bliss. Giddiness floated through him, feverish in its addictiveness to claim him. Really, he should have expected such a feat for his brother.  
  
Of course it stood to high chance he took another mate. From Sasuke’s own limited experience, he was talented. Despite the mocking he was sure to face for one-off sex and being less than satisfactory, he would brace himself to ignore the jibes that he was secondhand goods for someone he considered superior to him. The sadness would hurt (he was with him, and he had always wanted to be close to him—he didn’t want to think about the complications!). But could insults hurt worse than the exhausting heat pangs? The novelty of his own growing desperation for him, the roughness of him sheathed in him… He couldn’t deny that. It was _delicious_. For so long he had thought he would shoulder his heats and prove the fulfillment he needed in his life was his brother’s death. Not give up on revenge before lust twisted it and showed weakness. Well, he should have foreseen he would end up seized in his hold years ago.  
  
Arching under him, he threw his head back on his shoulder. Itachi, encouraged to make him writhe, clamped an arm low around his waist. The slap of his shaft against his wrist made the movement worth the effort. His other hand hit the boulder next to his and the pad of his palm dug in the sharpened edge for leverage. A trickle of blood graced his palm. Not caring, he sandwiched him firmly between surfaces. Sasuke flailed each time the cock throbbed with indescribable _hardness_ and gradually swelled. Itachi basked in the flurry of thrusts, groin finally coiling with pressure.  
  
Electric pinpricks bolted down Sasuke’s spine. Spasming, the orgasm soared through him. His groan was long and drawn out, and a trail of saliva fell past his lips and down his chin. He wasn’t surprised to be the first. He sagged against the boulder, head lopsided against the edge. Gasping, he breathed, failing to draw enough air in his lungs to calm himself down. He relied on the boulder for sole support and abandoned his footing even though he still swore he was falling into an abyss. Itachi’s harsh pants resounded in his eardrums.  
  
The bottom of his chin landed in his hair, and the immense build up crested. He rode out his high while his last thrusts were clumsy and short before giving into the wild calls of his darkest desire. Come spurted inside him and dripped down his thighs. He fell against his back, the pleasure sweeping through him. The head of his engorged knot inflated. Never had Sasuke felt something so quickly claim his body, or believe they would be intimately attached. The knot’s swell ebbed the heat in his veins and sate his every internal urge for release. While their orgasms subsided, the aches and pain ceased enough for him to remember he could feel normal. To his sheer chagrin he begrudgingly admitted Itachi had been right; his legs were not in the slightest bit ready to take signals for even feeling.  
  
Eyes steely with protectiveness, Itachi finally found the energy to wrap both arms around his waist for extra measure. The fishnet on his chest comfortably rested against his back. His palm landed on the skin his unbuttoned shirt did not cover, and Sasuke shuddered, the hand unmistakable on his bare chest.  
  
Temporarily, Itachi was satisfied. But in the long term he was nowhere near prepared to let him go. One time was not good enough to make up for the number of daydreams that led to it, especially when they were unlikely to meet in the near future again. It depended on… many factors. And Itachi keeping up the image capturing tailed beasts mattered more than his brother. Even then he was dedicated to keeping him as a mate until his death was within sight. (And he did not want to accept that, frankly—officially leaving him behind, his territorial alpha scent on him fading.) At that rate, the crows would keep watch, and that settled unease for missing his future heats.  
  
For the time being, a break was in order. The knot needed time to release. First times were exhausting, and he was at the whims of his depleted stamina. Straightening, Itachi’s plan to whisper sneers in Sasuke’s ear was foiled. Exposed and unmarked skin, soft and pale… The nape of his neck was a welcoming slope. A gentle, ingenuous plain of skin; it was the physical representation of his brother at the core of his heart. Except… The garish tomoe of his curse mark ruined the view. Irritation coursed within him. On second thought, he still couldn’t let him believe he was off the hook. He also had to be a good big brother and make sure he didn’t miss a single spot.  
  
The breath cascading his neck made him hiss. Still sensitive, he was nowhere recovered for more. His chin fell over the collar of his shirt, and his nose and lips dived underneath the rounded edge. Hair lightly tickled his nose. In the closed off space his scent was confined for his enjoyment. Sniffing, he basked in a new rush. Lips crashed on his unblemished skin, and he licked the hollow below the spikes of his hair and base of his neck.  
  
Jerking, the curve of his lips sent him reeling. The coarse ringlets of his necklace scraped his skin each time he leaned in over the hem of his collar a little farther and pinned the fabric. Tongue slid and caressed Sasuke’s neglected, smooth skin. He hadn’t thought it possible the wet heat could make him squirm and nearly beg after everything they did together.  
  
“Ah-hah… Hah…“ The clarity of mind he had regained was effectively thrown to the wind.  
  
With each tongue swipe he traced the column of bone and lowered to his shoulder blades. The cold metal of his headband lifted his hair up and chafed the bottom of his skull. His tongue lashed at the curse mark, circling all three tomoe in distinct, uneven outlines, until the seal faintly burned under the assault.  
  
_“Ngh_ —!“ Sasuke’s arms dropped to his sides, willfully letting whatever happened do so.  
  
Trailing his way back up, he bit and nipped the juncture between his neck and shoulder. Thorough bites on his scent glands turned into eager, sloppy kisses and sucks along the expanse of his back. Sasuke winced, though the thrill of flirting with danger made his stomach tie up in knots. He both feared and savored waking up with bruises that must be hidden from prying eyes the next day.  
  
“A reminder you submitted to me,” Itachi said. “You have a long path to walk, little brother.”  
  
The stab of annoyance for his cockiness still did not explain the goosebumps rising on his arms and the back of his neck at the words. Truly, he hated he was beyond irresistible, but he would bring himself to care later.


End file.
